Not Applicable.
Not Applicable.
The invention relates to a suture buttress and a system for deploying the suture buttress and manipulating a suture.
Open repair of the rotator cuff tendon is the most common open surgical procedure performed on the shoulder. It has been estimated that the incidence of rotator cuff tearing in the population at large runs between 15 and 25%, with approximately half of these being full thickness tears of the tendon. A smaller percentage of these become sufficiently symptomatic to warrant surgical repair.
Generally, techniques for repairing rotator cuff tears involve reattaching the torn tendon back to the bone from which it is avulsed. Typically, suture material is used to tie the tendon directly back to bone to facilitate healing of the tendon. Common technical problems with this repair often result from the fact that rotator cuff tears frequently occur in patients who are in an older age group. These patients often have poor quality bone, osteopenic bone, or bone that has been weakened by disuse due to pain. When the tendon is brought back to the bone, attempts to hold the tendon securely to the bone can be frustrated by the poor quality bone.
One method for reattaching the rotator cuff tendon to bone is to make a hole or tunnel in the bone of the greater tuberosity, to pass suture thread that has been secured to the tendon through these bone tunnels, and to reattach the rotator cuff tendon directly to the bone by tying these sutures. Using this method, the suture material can be frayed and weakened, or possibly severed, by contact with sharp edges of subcortical bone inside the bone tunnel or at the openings of the bone tunnel.
Poor bone quality also affects this method of repair adversely as the suture material may cut directly through the bone, frustrating the attempts at secure repair. Even where the suture does not cut completely through the bone, any amount of carving into bone by the suture material may result in a loosening of the suture and a corresponding loosening of the attachment of the rotator cuff tendon to bone.
The present invention provides a suture buttress system. The system of the invention has a suture retriever including a handle and an elongate member extending from the handle. The elongate member has an outer surface and a suture retaining element located at its distal end. The suture buttress system also includes a suture buttress composed of a resilient hollow tube having an outer surface and opposed ends. The suture buttress is removably and replaceably disposed on the elongate member of the suture retriever.
In one embodiment, the suture buttress includes an external fastening element made up of one or more slits formed in the outer surface of the suture buttress. The slits are formed at an angle to a plane transverse to a longitudinal axis of the suture buttress so that when the tube is flexed, such as when the tube is disposed on a curved portion of the suture retriever, at least one raised edge extends outward from the outer surface of the suture buttress. The slits may be angled so that the raised edges allow the suture buttress to slide into a bone tunnel in a first direction when urged into the tunnel by insertion of the suture retriever into the tunnel, but the raised edges engage the tunnel to prevent the suture buttress from sliding out of the tunnel in a direction opposite from the insertion direction.
Other external fastening elements useful with the suture buttress include resilient flanges disposed on the outer surface of the buttress and folding a portion of the tube adjacent to each of the opposed ends of the buttress over onto the outer surface of the buttress. A suture buttress deployment tool may also be removably and replaceably disposed on the outer surface of the suture retriever in proximity to the suture buttress.
The invention also provides a bone tunnel buttress. The bone tunnel buttress includes an elongate hollow tube having an outer surface and opposed proximal and distal ends. At least one external fastening member is formed on the outer surface of the tube. The bone tunnel buttress of the invention may be deployed within a bone tunnel so that the external fastening member prevents removal of the bone tunnel buttress from a bone tunnel in a direction opposite to a direction of insertion of the bone tunnel buttress.